A magnitude 7.8 earthquake centred north of Christchurch has jolted New Zealand and triggered a tsunami, possibly three to five metres high. So far only 2 people are known to have been killed in the earthquake.

The severe quake, located 15 km north-east of Culverden on South Island, struck just after midnight on Sunday and was felt throughout the country, along with several powerful aftershocks.

The first wave of the tsunami arrived at Kaikoura just before 2am on Monday local time, according to the NZ Ministry of Civil Defence and Emergency Management.

Prime Minister John Key confirmed at least two people have died in the earthquake. He said he ordered a military helicopter to the Kaikoura region which has been cut off.

He said: ‘We don’t have any indications at the moment to believe it will rise, but we can’t rule that out.’

The Civil Defence has warned ‘destructive waves’ will continue and people on the country’s east coast have been ordered to move to high ground. Although, those alerts have now been downgraded to ‘coastal warnings’.

The largest waves, between three to five metres high, were expected between Marlborough Peninsula near Wellington and Banks Peninsula, just south of Christchurch, according to Civil Defence.

Waves were also predicted to hit Chatham Island.

New Zealand lies on the Ring of Fire, a zone of areas prone to earthquakes and volcanic eruptions, that circles the Pacific rim.

Christchurch has not fully recovered from an earthquake in 2011 that killed 185 people.

Authorities have asked people in Wellington to stay away from work on Monday because of the dangers posed by aftershocks and the damage caused to some buildings.

The city’s suburban rail network has been shut while engineers inspect the tracks, bridges and tunnels for any damage.

‘We know this is scary. We are with you, New Zealand. Please look after each,’ NZ Government’s GeoNet posted on Twitter.

In several cities guests were forced to evacuate hotels when the quake hit, including Nelson, about 200 kilometres from the quake centre where the touring Pakistan cricket team are staying.

‘Some of the boys were in prayer, some were watching the India-England Test on TV when we felt the windows shake,’ team manager Wasim Bari told ESPNcricinfo.

‘The whole room began to shake. We were on the sixth and seventh floor, and evacuated immediately.’